Adding in comments and reworking how temp is read from CPU

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+# rpi-temp-control
+
+A temperature monitor and control program for the Raspberry Pi's CPU. This is done by monitoring the reported temperature
+of the combined CPU and GPU package, which is fed into a PID loop that controls the speed of a fan mounted above it.
+
+I wrote this so my Pi would be quite when it is doing simple tasks, but would be able to enable a fan to cool the CPU
+when I need to compile things or surf the web.
+
+# Using
+
+To run this program, you are going to need root privileges but can be run by simply entering
+
+```
+# python rpi-temp-control.py
+``` 
+
+This will leave the program running forever, and you should notice the fan changing speed as the Pi gets warmer and
+cooler. At some point I will turn this into a proper daemon service that can be setup and forgotten about.
+
+There are only a couple of things that should be noted when using this, first that you need to connect a fan to the Pi
+in a safe way. You should NOT drive the fan from the gpio pins on the Pi directly, but instead the pin that this
+program controls should be some sort of enable line on either a power transistor or motor control board. The second
+thing is that this program is writing a pwm signal to that pin, which means the fan is really turning on and off quickly
+and may make not allow this program to work with motor controllers that use other methods to control motor speed. Also
+be aware that there is probably a minimum speed (or pulse rate) that the fan will work at, so the minimum fan speed
+may need to be tweaked because of that.
+
+Please don't expect this to solve all overheating issues your Pi may experience, this just a dumb PID loop. Really any
+Raspberry Pi 3 (at least in my experience) should have at least a heatsink on their CPU to help with limiting when
+thermal throttling will happen. A case or mounting for a fan should have enough airflow for the fan so it won't burn out
+the motor, but if the air the fan is moving across the CPU will limit how cool it can make the CPU.
+# Copyright and License
+
+2018 Matt Kohls
+GPL v3
+
+Based on the work by [rudybrian](https://github.com/rudybrian/PID_Fan_Control)
+
+This program is distributed in the hope it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty
+of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
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